In order to maximize the performance and product life of an optoelectronic transceiver over a range of operating temperatures, the AC and DC bias levels of the optical transmitter module in the optoelectronic transceiver must be set at an optimal level for those temperatures within the operating range. These optimal levels correspond to operation where the “extinction ratio” and optical output power remain relatively constant. However, the operating characteristics of the laser diode in each transceiver module vary from module to module within a given product line. This variation prevents the utilization of global AC and DC bias settings throughout an entire product line whose components and configurations are otherwise identical. Therefore, the AC and DC bias levels for each module must be calibrated and set individually. Calibrating and setting the AC and DC bias levels of each individual laser diode for each transceiver is both expensive and time consuming.
Prior to the current invention, the AC and DC bias levels of a laser diode were set by using a test system that contains a digital communication analyzer (“DCA”). The DCA was used to monitor the optical output signal while varying the AC and DC bias levels of an optical transmitter module until the AC bias level that produces the optimal “extinction ratio” in the optical output signal is found. The DCA is a specialized oscilloscope with built-in software for measuring the “extinction ratio” of the laser diode. The primary disadvantage to using the DCA to set the AC and DC bias levels is cost—capital cost of the DCA itself and the time and costs associated with the configuration of the software and parameter settings of the test system. Furthermore, the test system is configured to only test and configure one optoelectronic transceiver at a time.
It would therefore be advantageous to have a method for setting the AC and DC bias levels of a laser diode without using a DCA. It would also be advantageous to provide a system and method capable of testing and configuring multiple optoelectronic transceivers simultaneously, without using a DCA.